The cloned antiplatelet IgGs bind specific to talin-H. (A) Fab D4 and D6 were tested for binding to murine GST-talin-H (1-435), murine GST-talin (36-1245), and a panel of other antigens by ELISA. (B) Western blot analysis of purified Fab D4 and D6 to GST-talin fusion proteins. GST constructs were visualized with an HRP-conjugated murine anti-GST Ab. Anti-gp120 Fab b12 was used as a negative control Ab, whereas the murine anti-human talin-H mAb TA205 was used as a positive control antibody. Lane 1, GST-talin 1-435; lane 2, GST-irrelevant peptide; lane 3, GST-talin 36-1245. (C) Titration of Fab D4 against purified human talin and recombinant GST-talin-H.